Crenchaw went from living the life of a college student to flying in the Civilian Pilot Training Program (CPTP). The CPTP was sponsored by the Army Air Corps. He was a flight instructor. After the start of World War II, there was a shortage of pilots. To combat this problem, then President Franklin D. Roosevelt, helped start a program to train more civilian pilots (thus increasing military preparedness). Crenchaw graduated in 1941 with his civilian pilot certificate from the Army Air Corps program sponsored by the Civil Aeronautics Administration.